One of the things I'd intended to do with this car (with the full approval of Mercedes-Benz, I should add quickly) was to take it drag racing. That arrangement fell through at the last minute, which was a pity, because I reckon it would have looked pretty impressive leaping away from the start line.And leap it certainly would have done. The Mercedes-AMG division has done its usual fine work here, giving the normally rather modest SLK a supercharged 3.2-litre engine which produces 348bhp. That's an awful lot for what is really quite a small car, and the result is storming straightline acceleration. Ideal for getting down a drag strip as quickly as possible, in fact. Oh, well.All the same, I did some experimenting to find the best way of getting the car off an imaginary start line. The accepted method on most cars with automatic transmission (there is no manual option for this model) is to stamp on each pedal and let go of the brake when you want to start rolling.This seemed a bit extreme for something with 348bhp, so I tried applying light pressure to each pedal instead. No good. The traction control system killed the engine immediately, and it was clear that switching it off would just produce vast amounts of wheelspin and tyre smoke but no forward motion. The quickest way of making a getaway seems to be the obvious one - leave the car ticking over until you want to move, and then push the loud pedal down to the carpet. Simple, but extremely effective.Anyway, back to the real world. AMG does not see its job as simply adding extra power, and in fact one feature of all the cars it has modified is that they are very docile when all you want to do is potter around.The SLK is no exception. You could kid a passenger into believing that it was no kind of a sports car, knowing all the while that one sharp press on the throttle pedal will have it hurtling towards the county boundary. I like this dual behaviour - so much so that I reckon it is one of the key features of any well set-up high-performance road car.When you're pressing on, the SLK proves to have a great deal of grip. The steering may feel vague to some people - it doesn't seem much different from that of a standard Mercedes saloon - but it's more precise than it appears to be. Ride quality is amazingly good considering how much effort has gone in to harnessing all that power, but there is no way of fully disguising the fact that this is a short car in which you sit almost on top of the rear axle. A certain bounciness is inevitable.The short wheelbase also means that cockpit room is quite limited. For anyone over six feet (or anyone who likes to drive with the seat reclined a long way) this presents something of a problem. I couldn't find a position I was comfortable with, and even on trips of modest length I found that my back was starting to hurt. For shorter drivers this shouldn't be much of a problem, since the seats seem supportive enough for the job.Occupant size considerations aside, the SLK AMG is a car that would be very easy to live with. In addition to the qualities listed above, build quality is up to traditional Mercedes standards, and fuel economy is reasonable in the circumstances.Oh, and the electro-hydraulically operated roof will remove itself from sight in 25 seconds. But you'll forgive me if I didn't go to the extent of driving the car with the roof down, won't you? I mean, it is October, after all.Second opinion: Yes, Mercedes-AMG does a remarkable all-things-considered job, and it would be a big mistake to regard this as just a performance conversion. There are many neat touches in the cabin, like the barely perceptible twin-tone effect of the leather trim, and the beautiful feel of the leather-rimmed steering wheel. On the road, you can drive this untemperamental car quite modestly, giving no impression that it has such a formidable power-to-weight ratio, but as the revs rise and the background supercharger whine suddenly appears in the foreground, all the AMG handling modifications come into their own. Pity about the tall-driver seating problem, but there's nothing AMG could do about that, or about the very restricted luggage space when the steel roof is retracted into the boot. Ross Finlay. Engine 3199cc, 6 cylinders Power 348bhp Fuel/CO2 25.2mpg / 268g/km Acceleration 0-62mph: 5.2 seconds Top speed 155mph Price £44,460 Details correct at publication date
